title: Self-induced mode transformation in nonlocal nonlinear media.
abstract: We report on the first experimental observation of self-induced optical mode transformations in nonlocal nonlinear media. We show that the quadrupole Hermite-Gaussian mode experiences complex nonlinear dynamics in a nematic liquid crystal, including power-dependent conversion into a radially symmetric Laguerre-Gaussian mode. The physical mechanism responsible for self-induced transformation is the excitation of internal modes of a metastable quadrupole nonlocal soliton and its subsequent transmutation into a robust soliton with a bright peak surrounded by a bright ring. We also observe the onset of transformations of higher-order modes, proving the generic character of this nonlinear phenomenon.
authors.affiliation: Nonlinear Physics Center, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: Yana V
authors.initials: YV
authors.lastname: Izdebskaya
authors.forename: Anton S
authors.initials: AS
authors.lastname: Desyatnikov
authors.forename: Yuri S
authors.initials: YS
authors.lastname: Kivshar